2530
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 10
- Digital Root
- 1
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 16
- Divisor Sum
- 5184
- Proper Divisor Sum (Aliquot Sum)
- 2654
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Highly Composite
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- yes
Derived Values
- Euler's Totient
- 880
- Möbius Function
- 1
- Radical
- 2530
- Omega Function (Ω)
- 4
- Little Omega Function (ω)
- 4
Special
- Factorial
- no
- Catalan Number
- no
- Bell Number
- no
- Motzkin Number
- no
- Primorial
- no
Figurate Numbers
- Fibonacci Number
- no
- Triangular Number
- no
- Perfect Square
- no
- Perfect Cube
- no
- Pentagonal Number
- no
- Hexagonal Number
- no
- Lucas Number
- no
- Tetrahedral Number
- no
- Pell Number
- no
- Tribonacci Number
- no
- Pronic Number
- no
Recreational
- Happy Number
- no
- Harshad Number
- yes
- Narcissistic Number
- no
- Collatz Steps
- 40
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- Squarefree Number
- yes
- Prime Power
- no
- Prime Factorization
- no
- Twin Prime
- no
- Mersenne Prime
- no
- Sophie Germain Prime
- no
- Safe Prime
- no
- Powerful Number
- no
- Achilles Number
- no
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- yes
- Odd
- no
Appears in sequences
- Number of rooted simplicial 3-polytopes with n+3 nodes; or rooted 3-connected triangulations with 2n+2 faces; or rooted 3-connected trivalent maps with 2n+2 vertices.at n=6A000260
- Fermat coefficients.at n=10A000970
- a(n) = 3^n + n^3.at n=7A001585
- a(n) = 7^n + n^7.at n=3A001596
- a(n) = binomial(5*n, n)/(4*n + 1).at n=5A002294
- Primitive pseudoperfect numbers.at n=39A006036
- Primitive nondeficient numbers.at n=32A006039
- 4-dimensional analog of centered polygonal numbers.at n=9A006322
- a(n) = n*(n+1)*(n+8)/6.at n=22A006503
- a(n) = (n^4 + n^2 + 2*n)/4.at n=10A006528
- Numbers k for which 10k+1, 10k+3, 10k+7 and 10k+9 are primes.at n=20A007811
- Molien series for cyclic group of order 5.at n=21A008646
- a(n) = floor(C(n,4)/5).at n=25A011795
- a(n) = floor( n*(n-1)*(n-2)/20 ).at n=38A011902
- a(n) = Sum_{k=1..n} floor(k^4/n).at n=9A014819
- Number of partitions of n into parts of 22 kinds.at n=3A023020
- Numbers k such that Fibonacci(k) == -55 (mod k).at n=41A023170
- a(n) = a(1)*a(n-1) + a(2)*a(n-2) + ...+ a(n-1)*a(1) for n >= 5, with initial values 2,1,1,1.at n=8A025269
- Triangle, T(n, k): T(n,k) = 1 for n < 3, T(3,1) = T(3,2) = T(3,3) = 2, T(n,0) = 1, T(n,1) = n-1, T(n,n) = T(n-1,n-2) + T(n-1,n-1), otherwise T(n,k) = T(n-1,k-2) + T(n-1,k-1) + T(n-1,k), read by rows.at n=72A026268
- a(n) = T(2n-1,n), where T is the array in A026268.at n=4A026291